Dendrochronology

Dendrochronology is the method of scientific dating based on the analysis of tree ring patterns. Trees develop yearly tree rings of different thickness depending on weather, rain, temperature, etc. in different years. Trees from the same region will tend to develop the same patterns of width for a given period.

Laboratory analysis of timber core samples measures the width of annual rings. By taking samples from different sites and different strata[?] within a particular region, researchers can build a comprehensive historical sequence that becomes a part of the scientific record. Some trees are more suitable than others for this type of analysis. For dating purposes, in some regions sequences of more than 10,000 years are available.